In the pulp industry, the wood used as raw material is cut into chips as required for the production process. Besides external dimensions, the chips must be of the right quality with respect to other properties as well. The chips are conveyed into a steaming silo and from there further to the pulping process. In the silo, the moisture of the chips is adjusted to a suitable level by supplying steam into the silo. At the same time, the air among the chips, which is detrimental to the pulping process, is removed.
In previously known technology, the steam is passed into the silo via steam pipes with nozzles placed at different heights on the silo walls or on the bottom of the silo. In these solutions, the steam is unevenly distributed in different parts of the silo, because the area close to the nozzle receives the most steam while the areas farthest away, especially in the horizontal direction, receives the least steam. To achieve uniform moisture, the pressure or amount of steam or the number of steam pipes and nozzles has to be increased. Both solutions are expensive to implement and they also increase the number of parts requiring service.